Mailman 3 - SfePy - python.org

ANN: SfePy 2024.4
by Robert Cimrman Dec. 29, 2024

Dec. 29, 2024

I am pleased to announce the release of SfePy 2024.4. Description ----------- SfePy (simple finite elements in Python) is a software for solving systems of coupled partial differential equations by finite element methods. It is distributed under the new BSD license. Home page: https://sfepy.org Mailing list: https://mail.python.org/mm3/mailman3/lists/sfepy.python.org/ Git (source) repository, issue tracker: https://github.com/sfepy/sfepy Highlights of this release -------------------------- - MUMPS solver interface moved to new mumpspy package, python-mumps support - new contact term based on IPC toolkit For full release notes see [1]. Cheers, Robert Cimrman [1] http://docs.sfepy.org/doc/release_notes.html#id1 --- Contributors to this release in alphabetical order: Robert Cimrman jidhub Vladimir Lukes

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Homohgenization with general microtensor fields
by Alexandros STATHAS Nov. 22, 2024

Nov. 22, 2024

Dear all, I am a new user of sfepy that was attracted to this FE code because of the homogenization engine. I am trying to solve a microproblem using the homogenization engine of sfepy. In my case the microsopic variable is not a vector -like $u^1_i$- but a tensor $\omega^1_{ij}$. As I understand sfepy provides the CorrDimDim class for storing the resulting microfield for the differnt unitary loads (pis). This class works fine if the unknown is a vector, but in my case it is a second order tensor how can I implement a Corr2Dim2Dim class or even more general CorrNDimMDim class for storing the values of more general fields? Thank you in advance for your help,

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ANN: SfePy 2024.3
by Robert Cimrman Sept. 30, 2024

Sept. 30, 2024

I am pleased to announce the release of SfePy 2024.3. Description ----------- SfePy (simple finite elements in Python) is a software for solving systems of coupled partial differential equations by finite element methods. It is distributed under the new BSD license. Home page: https://sfepy.org Mailing list: https://mail.python.org/mm3/mailman3/lists/sfepy.python.org/ Git (source) repository, issue tracker: https://github.com/sfepy/sfepy Highlights of this release -------------------------- - updated installation instructions - new Stokes traction term For full release notes see [1]. Cheers, Robert Cimrman [1] http://docs.sfepy.org/doc/release_notes.html#id1 --- Contributors to this release in alphabetical order: Robert Cimrman Vladimir Lukes

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ANN: SfePy 2024.2
by Robert Cimrman June 28, 2024

June 28, 2024

I am pleased to announce the release of SfePy 2024.2. Description ----------- SfePy (simple finite elements in Python) is a software for solving systems of coupled partial differential equations by finite element methods. It is distributed under the new BSD license. Home page: https://sfepy.org Mailing list: https://mail.python.org/mm3/mailman3/lists/sfepy.python.org/ Git (source) repository, issue tracker: https://github.com/sfepy/sfepy Highlights of this release -------------------------- - multi-point constraints terms + new example - mixed formulation flexoelecticity terms - improved and new eigenvalue problem solvers For full release notes see [1]. Cheers, Robert Cimrman [1] http://docs.sfepy.org/doc/release_notes.html#id1 --- Contributors to this release in alphabetical order: Robert Cimrman Florian Le Bourdais Vladimir Lukes

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Bugs in test after installing sfepy
by CARLIOZ Thomas June 25, 2024

June 25, 2024

Hello, I'm writing to you because I experience some difficulties to install properly sfepy ... First, I use Anaconda and I am in a windows environment. I created a new environment to do the install with Python 3.12.4 in it. When I tried to install sfepy through conda install -c conda-forge sfepy commands it didn't go through. Instead, I used pip install which finished properly. I also installed pytest with pip install pytest but when I run sfepy-test I have several errors. I can't find site_cfg.py files to edit it, as required in the debugging section. So I can only copy paste what the output of the sfepy-test command is (see below the email). Could you help me ? Regards, Thomas Carlioz ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ platform win32 -- Python 3.12.4, pytest-8.2.2, pluggy-1.5.0 rootdir: C:\Users\TC269207\AppData\Local\anaconda3\envs\sfepy\Lib\site-packages\sfepy collected 172 items / 9 errors ======================================================= ERRORS ======================================================== _______________________________________ ERROR collecting tests/test_dg_field.py _______________________________________ tests\test_dg_field.py:5: in <module> from sfepy.discrete.fem import FEDomain discrete\__init__.py:9: in <module> from .variables import (Variables, Variable, FieldVariable, DGFieldVariable, discrete\variables.py:20: in <module> from sfepy.discrete.fem.lcbc_operators import LCBCOperators discrete\fem\__init__.py:11: in <module> from .fields_base import Field discrete\fem\fields_base.py:26: in <module> from sfepy.discrete.fem.mappings import FEMapping discrete\fem\mappings.py:9: in <module> from sfepy.discrete.common.mappings import Mapping, PyCMapping discrete\common\mappings.py:7: in <module> from sfepy.discrete.common.extmods.cmapping import CMapping cmapping.pyx:1: in init sfepy.discrete.common.extmods.cmapping ??? E ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from PyObject ____________________________________ ERROR collecting tests/test_dg_terms_calls.py ____________________________________ tests\test_dg_terms_calls.py:11: in <module> from sfepy.discrete import DGFieldVariable, Material, Integral discrete\__init__.py:9: in <module> from .variables import (Variables, Variable, FieldVariable, DGFieldVariable, discrete\variables.py:20: in <module> from sfepy.discrete.fem.lcbc_operators import LCBCOperators discrete\fem\__init__.py:11: in <module> from .fields_base import Field discrete\fem\fields_base.py:26: in <module> from sfepy.discrete.fem.mappings import FEMapping discrete\fem\mappings.py:9: in <module> from sfepy.discrete.common.mappings import Mapping, PyCMapping discrete\common\mappings.py:7: in <module> from sfepy.discrete.common.extmods.cmapping import CMapping cmapping.pyx:1: in init sfepy.discrete.common.extmods.cmapping ??? E ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from PyObject ________________________________________ ERROR collecting tests/test_domain.py ________________________________________ tests\test_domain.py:7: in <module> from sfepy.discrete.fem import Mesh, FEDomain discrete\__init__.py:9: in <module> from .variables import (Variables, Variable, FieldVariable, DGFieldVariable, discrete\variables.py:20: in <module> from sfepy.discrete.fem.lcbc_operators import LCBCOperators discrete\fem\__init__.py:11: in <module> from .fields_base import Field discrete\fem\fields_base.py:26: in <module> from sfepy.discrete.fem.mappings import FEMapping discrete\fem\mappings.py:9: in <module> from sfepy.discrete.common.mappings import Mapping, PyCMapping discrete\common\mappings.py:7: in <module> from sfepy.discrete.common.extmods.cmapping import CMapping cmapping.pyx:1: in init sfepy.discrete.common.extmods.cmapping ??? E ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from PyObject ______________________________________ ERROR collecting tests/test_ed_solvers.py ______________________________________ tests\test_ed_solvers.py:7: in <module> from sfepy.mesh.mesh_generators import gen_block_mesh mesh\mesh_generators.py:12: in <module> from sfepy.mesh.mesh_tools import elems_q2t mesh\mesh_tools.py:1: in <module> from sfepy.discrete.fem import Mesh, FEDomain discrete\__init__.py:9: in <module> from .variables import (Variables, Variable, FieldVariable, DGFieldVariable, discrete\variables.py:20: in <module> from sfepy.discrete.fem.lcbc_operators import LCBCOperators discrete\fem\__init__.py:11: in <module> from .fields_base import Field discrete\fem\fields_base.py:26: in <module> from sfepy.discrete.fem.mappings import FEMapping discrete\fem\mappings.py:9: in <module> from sfepy.discrete.common.mappings import Mapping, PyCMapping discrete\common\mappings.py:7: in <module> from sfepy.discrete.common.extmods.cmapping import CMapping cmapping.pyx:1: in init sfepy.discrete.common.extmods.cmapping ??? E ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from PyObject __________________________________ ERROR collecting tests/test_eigenvalue_solvers.py __________________________________ tests\test_eigenvalue_solvers.py:5: in <module> from sfepy.mesh.mesh_generators import gen_block_mesh mesh\mesh_generators.py:12: in <module> from sfepy.mesh.mesh_tools import elems_q2t mesh\mesh_tools.py:1: in <module> from sfepy.discrete.fem import Mesh, FEDomain discrete\__init__.py:9: in <module> from .variables import (Variables, Variable, FieldVariable, DGFieldVariable, discrete\variables.py:20: in <module> from sfepy.discrete.fem.lcbc_operators import LCBCOperators discrete\fem\__init__.py:11: in <module> from .fields_base import Field discrete\fem\fields_base.py:26: in <module> from sfepy.discrete.fem.mappings import FEMapping discrete\fem\mappings.py:9: in <module> from sfepy.discrete.common.mappings import Mapping, PyCMapping discrete\common\mappings.py:7: in <module> from sfepy.discrete.common.extmods.cmapping import CMapping cmapping.pyx:1: in init sfepy.discrete.common.extmods.cmapping ??? E ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from PyObject ________________________________ ERROR collecting tests/test_homogenization_engine.py _________________________________ tests\test_homogenization_engine.py:3: in <module> from sfepy.homogenization.engine import HomogenizationEngine as he homogenization\engine.py:6: in <module> from sfepy.applications import PDESolverApp, Application applications\__init__.py:3: in <module> from .pde_solver_app import PDESolverApp, solve_pde, assign_standard_hooks applications\pde_solver_app.py:7: in <module> from sfepy.discrete import Problem discrete\__init__.py:9: in <module> from .variables import (Variables, Variable, FieldVariable, DGFieldVariable, discrete\variables.py:20: in <module> from sfepy.discrete.fem.lcbc_operators import LCBCOperators discrete\fem\__init__.py:11: in <module> from .fields_base import Field discrete\fem\fields_base.py:26: in <module> from sfepy.discrete.fem.mappings import FEMapping discrete\fem\mappings.py:9: in <module> from sfepy.discrete.common.mappings import Mapping, PyCMapping discrete\common\mappings.py:7: in <module> from sfepy.discrete.common.extmods.cmapping import CMapping cmapping.pyx:1: in init sfepy.discrete.common.extmods.cmapping ??? E ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from PyObject _____________________________________ ERROR collecting tests/test_projections.py ______________________________________ tests\test_projections.py:6: in <module> from sfepy.discrete import FieldVariable discrete\__init__.py:9: in <module> from .variables import (Variables, Variable, FieldVariable, DGFieldVariable, discrete\variables.py:20: in <module> from sfepy.discrete.fem.lcbc_operators import LCBCOperators discrete\fem\__init__.py:11: in <module> from .fields_base import Field discrete\fem\fields_base.py:26: in <module> from sfepy.discrete.fem.mappings import FEMapping discrete\fem\mappings.py:9: in <module> from sfepy.discrete.common.mappings import Mapping, PyCMapping discrete\common\mappings.py:7: in <module> from sfepy.discrete.common.extmods.cmapping import CMapping cmapping.pyx:1: in init sfepy.discrete.common.extmods.cmapping ??? E ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from PyObject ______________________________________ ERROR collecting tests/test_ref_coors.py _______________________________________ tests\test_ref_coors.py:7: in <module> import sfepy.discrete.common.global_interp as gi discrete\common\global_interp.py:9: in <module> import sfepy.discrete.common.extmods.crefcoors as crc crefcoors.pyx:1: in init sfepy.discrete.common.extmods.crefcoors ??? E ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from PyObject ______________________________________ ERROR collecting tests/test_splinebox.py _______________________________________ tests\test_splinebox.py:5: in <module> from sfepy.discrete.fem import Mesh discrete\__init__.py:9: in <module> from .variables import (Variables, Variable, FieldVariable, DGFieldVariable, discrete\variables.py:20: in <module> from sfepy.discrete.fem.lcbc_operators import LCBCOperators discrete\fem\__init__.py:11: in <module> from .fields_base import Field discrete\fem\fields_base.py:26: in <module> from sfepy.discrete.fem.mappings import FEMapping discrete\fem\mappings.py:9: in <module> from sfepy.discrete.common.mappings import Mapping, PyCMapping discrete\common\mappings.py:7: in <module> from sfepy.discrete.common.extmods.cmapping import CMapping cmapping.pyx:1: in init sfepy.discrete.common.extmods.cmapping ??? E ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from PyObject =============================================== short test summary info =============================================== ERROR tests/test_dg_field.py - ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from P... ERROR tests/test_dg_terms_calls.py - ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from P... ERROR tests/test_domain.py - ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from P... ERROR tests/test_ed_solvers.py - ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from P... ERROR tests/test_eigenvalue_solvers.py - ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from P... ERROR tests/test_homogenization_engine.py - ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from P... ERROR tests/test_projections.py - ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from P... ERROR tests/test_ref_coors.py - ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from P... ERROR tests/test_splinebox.py - ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from P... !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Interrupted: 9 errors during collection !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! ================================================= 9 errors in 12.97s ==================================================

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ANN: SfePy 2024.1
by Robert Cimrman March 29, 2024

March 29, 2024

I am pleased to announce the release of SfePy 2024.1. Description ----------- SfePy (simple finite elements in Python) is a software for solving systems of coupled partial differential equations by finite element methods. It is distributed under the new BSD license. Home page: https://sfepy.org Mailing list: https://mail.python.org/mm3/mailman3/lists/sfepy.python.org/ Git (source) repository, issue tracker: https://github.com/sfepy/sfepy Highlights of this release -------------------------- - new constant-in-a-region field approximation. - new term: passive large deformation fibres with exponential elastic response - improved solver status reporting - wedge elements + example - multi-node linear combination (boundary) conditions + example For full release notes see [1]. Cheers, Robert Cimrman [1] http://docs.sfepy.org/doc/release_notes.html#id1 --- Contributors to this release in alphabetical order: Robert Cimrman Vladimir Lukes

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Question about using sfepy
by Hongwei Wu Jan. 17, 2024

Jan. 17, 2024

Hi, everyone. I am starting to solve a chemomechanical problem, but I don't know whether the fully coupled equations can be solved in sfepy or not. Could you have a look at them? The equation are as followed: Governing Equations ∇∙σ+ρb=ρu ̈ Where σ is the stress tensor, ρ is the mass density, b is the body force per unit mass, u is the displacement vector. ∂c/∂t+∇∙j=∂r/∂t, where j=-(D*c_0)/RT ∇Ψ Where c is the concentration, D is the diffusion coefficient, c0 is the reference concentration, R is Boltzmann constant (gas constant), T is the absolute temperature, Ψ is the chemical potential. Constitutive relations σ=2Gε+(λe+bc)I Ψ=be+gc Where b=-β(2G+3λ), β is the chemical dilation coefficient, e is the volumetric strain and g represents the scalar chemistry modulus.

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pseudo-2D Geometry to current flow
by Steve Spicklemire Jan. 4, 2024

Jan. 4, 2024

Hello SfePy folks, It’s been a long time (e.g., 10+ years) since I tinkered with SFEPY, but I dug out my old calculations and with a bit of tweaking, they still work. Yeah! Thank you for keeping on for so long with this excellent tool for python! I’m hoping you can lend me some guidance for a new calculation. I’m interested in using SfePy to answer questions about the behavior of PCB traces. For example, I’d like to be able to extract a trace from a Gerber file and convert it into a mesh that SfePy can grok. I can figure out the file conversion, I think. If nothing else I can fake it using the gmsh “geo” format. However, then I’d like to compute the current flow through the mesh with a fixed voltage difference between two boundaries while maintaining a zero current boundary condition on all the other boundaries. Is that a thing that could be done? Any suggestions on how to go about setting up the boundary conditions? Thank you, -Steve

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ANN: SfePy 2023.4
by Robert Cimrman Dec. 28, 2023

Dec. 28, 2023

I am pleased to announce the release of SfePy 2023.4. Description ----------- SfePy (simple finite elements in Python) is a software for solving systems of coupled partial differential equations by finite element methods. It is distributed under the new BSD license. Home page: https://sfepy.org Mailing list: https://mail.python.org/mm3/mailman3/lists/sfepy.python.org/ Git (source) repository, issue tracker: https://github.com/sfepy/sfepy Highlights of this release -------------------------- - new structural elements: linear spring, linear truss - spectral element method (LGL quadrature and nodes with Lagrange basis) - initial support for meshes with elements of different topological dimensions - new examples: 2D and 3D truss bridge, h-refinement eigenvalue convergence, beam consisting of hexa and tetra elements - many more examples included in gallery For full release notes see [1]. Cheers, Robert Cimrman [1] http://docs.sfepy.org/doc/release_notes.html#id1 --- Contributors to this release in alphabetical order: Robert Cimrman Florian Le Bourdais Vladimir Lukes

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Re: Fwd: How to implement hydroststic stress in Sfepy?
by Robert Cimrman Dec. 22, 2023

Dec. 22, 2023

Hello, On 12/16/23 13:51, Himalaya singh wrote: > Hello sir, > I sent you what you asked earlier, these are the files. > I was trying to implement time dependent boundary conditions, that is in > stress diffusion two way coupling and I am getting issues. Can you please > help me in correcting issues I am encountering. > where, in file C= concentration and i am trying to build lithium-ion > diffusion interaction. > Here, I want to know how to implement time dependent boundary conditions > and hydrostatic stress. I don't have any idea how to use hydrostatic stress > using Sfepy. OK, now I can run it with the mesh you sent me. In your Jupyter notebook you had several cells defining the same objects and the later definitions clashed/overwritten the previous. I have cleaned it up (see attachment), so it would be a good idea to put all the code into a function, so that things are defined in a single place. The main problem with your get_displacement() function was that its value depended on coors[:, 0], which was zero. It also did not depend on time... So I replaced displacement = [-(c_max - c_min)/2 * np.cos(np.pi) + (c_max + c_min)/2]* coors[:, 0] with displacement = [-(c_max - c_min)/2 * np.cos(np.pi) + (c_max + c_min)/2]* coors[:, 1] * 0.001 * time and the conditions change in time. Ad hydrostatic stress: what is the test function (omega?) in your term? Is it a scalar? Anyway, have a look at the Hooke's law [1], when defined using the bulk modulus K, and shear modulus G. Now just set G = 0, and you have the hydrostatic part... So there is a good chance that you can use the a sfepy term that involves the Cauchy stress, only set its material parameters so that G = 0. You use the Lame's parameters, so just set mu = 0, as mu is G [2]. Or maybe dw_piezo_coupling could be hacked for your purpose by appropriately tailoring the material tensor, depending on what your test function is. r. [1] https://en.wikipedia.org/wiki/Hooke%27s_law#Linear_elasticity_theory_for_co… [2] https://en.wikipedia.org/wiki/Lam%C3%A9_parameters

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